#include <stdio.h>
struct st {
    int st;
};

struct st st(struct st st) {
    st.st = 2;
    return st;
}


int main()
{
    struct st st;

    st.st = 1;
    printf("st.st=%d.\n", st.st);

    st = st(st);
    printf("st.st=%d.\n", st.st);

    return 0;
}
